Detection of Transient Increase of Cerebral Blood Flow and Reversible Neuronal Dysfunction by Iodine-123-Iomazenil Single Photon Emission Computed Tomography After Cerebral Hyperperfusion Syndrome After Revascularization Surgery for Moyamoya Disease.

Background: Early and late images of single photon emission computed tomography (SPECT) using I-iomazenil (I-IMZ) can demonstrate cerebral blood flow and cortical neuronal viability. Hyperperfusion syndrome is one of the serious complications after revascularization surgery for moyamoya disease; therefore, the real-time observation of the hemodynamics and neuronal viability is important for the treatment after the revascularization. Here we report, a case of moyamoya disease where I-IMZ SPECT had a significant efficacy to delineate the hemodynamics and transient neuronal dysfunction in hyperperfusion state after revascularization.

Case Description: A 47-year-old woman presented with motor aphasia 3 days after superficial temporal artery-middle cerebral artery anastomosis with indirect revascularization. Magnetic resonance imaging (MRI) on the same day showed no new ischemic changes but high intensities along the left frontal sulci observed on fluid-attenuated inversion recovery images, and I-IMZ SPECT demonstrated the increased uptake on the early images and the decreased uptake on the late images around the anastomosis site. The patient was completely recovered 1 month after surgery, and abnormal changes on MRI and I-IMZ SPECT returned to normal along with the symptom withdrawal.

Conclusions: These findings indicate that I-IMZ SPECT could be the index for the treatment of revascularization for obstructive vascular diseases such as moyamoya disease.